Dr. Xu received his medical degree in 1986, Master of Science degree in 1992 and a Ph.D degree in 1998 from Shanghai Institute of Neuroscience of Chinese Academy of Sciences. He came to the University of Texas Medical Branch as a visiting scientist and postdoctoral fellow in 1998. In 2004, Dr. Xu became an Instructor at the Division of Gastroenterology in the Department of Internal Medicine. He was promoted to Assistant Professor in 2005.

Dr. Xu's research interest is to understand the roles and mechanisms of ion channels and receptors in sensory afferent neurons in chronic viscreal hyperalgesia associated with variety of gastrointestinal diseases, such as irritable bowel syndrome (IBS), inflammatory bowel disease, chronic pancreatitis and gastric ulcers. His research efforts include in evaluation of currents of voltage-gated ion channels and ligand-gated receptor channels and in measurement of protein and mRNA expression of the same, using whole cell patch clamp techniques, advanced optical imaging system, and laser capture microdissection and RT-PCR. His recent studies demonstrated that the excitability of organ-specific sensory neurons was greatly enhanced in the rat models of IBS and chronic pancreatitis, which may be mediated by the reduction in currents of voltage-gated potassium channels. He also demonstrated that TRPV1 and P2X receptors were sensitized in these diseases and that these key molecules may play an important roles in the development and maintenance of chronic visceral hyperalgesia. It is hoped that these studies will provide valuable insight into the potential therapeutic value of drugs in the management of inflammatory and neuropathic pain.

Xu G-Y, Shenoy M, Winston J H, Mittal, S. and Pankaj J Pasricha. P2X receptor-mediated visceral hyperalgesia in a rat model of chronic visceral hypersensitivity. GUT, (Published Online, Feb. 12, 2008) 2. Xu G-Y, Winston J H, Shenoy M, Yin H and Pasricha P J. Transient Receptor Potential Vanilloid 1 Mediates Hyperalgesia and Is Up-Regulated in Rats With Chronic Pancreatitis. Gastroenterology, 133(4):1282-1292, 2007. 3. Xu G-Y, Winston J H, Shenoy M,.Yin H. and Pasricha PJ. Enhanced excitability and suppression of A-type potassium current of pancreas specific afferent neurons in a rat model of chronic pancreatitis. Am J Physiol-Gastrointest Liver Physiol, 291:424-431, 2006. 4. Xu G-Y and Huang L-Y M. Calcium/calmodulin-dependent protein kinase II potentiates ATP responses by promoting trafficking of P2X receptors. Proc. Natl. Acad. Sci. U. S. A. 101(32):11868-11873, 2004. 5. Xu Y, Gu Y-P, Xu G-Y, Li G-W, Wu P and Huang L-Y M. Adeno-associated viral transfer of opioid receptor gene to primary sensory neurons: A strategy to increase opioid antinociception. Proc. Natl. Acad. Sci. U. S. A. 100: 6204-6209, 2003. 6. Xu G-Y and Zhao Z-Q. Cross-inhibition of mechanoreceptive inputs in peripheral inflammatory cat. Brain Research, 970 (1-2):188-194, 2003. 7. Xu G-Y and Huang L-Y M. Peripheral inflammation sensitizes P2X-receptor mediated responses in rat dorsal root ganglion neurons. Journal of Neuroscience, 22(1):93-102, 2002. 8. Xu G-Y and Zhao Z-Q. Changes in excitability and phenotype of substance P and its receptor in cat sensory neurons following peripheral inflammation. Brain Research, 923(1-2): 112-119, 2001. 9. Xu G-Y, Huang L-Y M and Zhao Z-Q. Activation of silent mechanoreceptive cat C and A-delta sensory neurons and their SP expression following peripheral inflammation. Journal of Physiology (Lond.), 528:339-348, 2000.

Address:	301 University Blvd., Galveston, Tx. 77555-0764
Email:	gyxu@utmb.edu
Office:	409-772-1501